U.S. patent number 4,218,702 [Application Number 05/905,605] was granted by the patent office on 1980-08-19 for means for remote control of an aircraft video system for surveying ground activity.
This patent grant is currently assigned to Societe Nationale Industrielle. Invention is credited to Francois Brocard, Andre Denizot, Marcel Dif.
United States Patent |
4,218,702 |
Brocard , et al. |
August 19, 1980 |
Means for remote control of an aircraft video system for surveying
ground activity
Abstract
A method of remote control of an aircraft video system and means
especially adapted for carrying out said method. An aircraft
carries a technical container comprising at least one TV camera
monitored by a TV screen and remotely controlled by a control box
in the pilot's cockpit. On the ground there are disposed an
orientable aerial, a receiver, a remote-control box for the aerial,
a VHF microphone and a magnetoscope. By using this system an
operator in the aircraft can both keep stability of the image
transmitted to the ground and monitor it by enlargement on the
monitor TV screen through instinctive reaction upon the
remote-control box in the cockpit. The operator can act on his own
initiative or on instructions being received from the ground or
possibly by way of a duplex system.
Inventors: |
Brocard; Francois (Paris,
FR), Denizot; Andre (Le Perreux, FR), Dif;
Marcel (Orsay, FR) |
Assignee: |
Societe Nationale Industrielle
(Paris, FR)
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Family
ID: |
9190984 |
Appl.
No.: |
05/905,605 |
Filed: |
May 12, 1978 |
Foreign Application Priority Data
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May 18, 1977 [FR] |
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77 15221 |
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Current U.S.
Class: |
348/144; 200/6A;
348/211.4; 396/12 |
Current CPC
Class: |
B64D
47/08 (20130101); G08G 1/04 (20130101) |
Current International
Class: |
B64D
47/00 (20060101); B64D 47/08 (20060101); G08G
1/04 (20060101); G08G 1/01 (20060101); H04N
007/18 () |
Field of
Search: |
;358/103,109,229,87,210,222 ;200/6A ;354/74 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1959941 |
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Jun 1971 |
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DE |
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844430 |
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Jul 1939 |
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FR |
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2175601 |
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Oct 1973 |
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FR |
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2265616 |
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Mar 1974 |
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FR |
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Other References
Airborne Surveillance System-Microwave Journal-Feb. 1971, p. 69.
.
Shigeta et al.-Design of the NHK Helicopter Color Camera System-NHK
Tech. Jour. (Japan) vol. 23, No. 2, 1971..
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Primary Examiner: Griffin; Robert L.
Assistant Examiner: Orsino, Jr.; Joseph A.
Attorney, Agent or Firm: Flocks; Karl W.
Claims
We claim:
1. An aircraft video system utilizing an aircraft and operation on
board intended for air surveyance of ground activity comprising
a technical container attached to the aircraft,
a transparent radome forming a forward portion of said
container,
a pilot camera inclinable in angle of sight and azimuth located in
said radome,
a television monitor screen in the aircraft connected to said
camera,
a remotely controlled inclination means for controlling inclination
and for controlling the object-lens of said camera in said radome
connected to said camera,
a television transmitter with its transmission aerial in a rearward
portion of said container,
said remotely controlled means including
a structure secured to said container through damping means,
a cradle connected to said structure,
a first means for pivoting said camera in azimuth with respect to
said cradle,
a second means for pivoting in sight said cradle with respect to
said structure,
electric motors having pulleys with two directions of rotation
connected to further pulleys linked to said camera, and said
electric motors also connected through cables to said cradle,
a remote-control box connected to said remotely controlled means
located to be acted upon by instinctive reaction of the operator
while observing said television monitor screen,
said remote-control box including
a pivoted axis shaft pivoted in an elastic block,
four microswitches controlling said electric motors for controlling
camera inclination,
said shaft having a lower portion which acts upon said
microswitches,
a plate in said box having a psuedo-square opening therein,
said lower portion of said shaft having protuberant parts on either
side of a portion of said shaft itself included in said
psuedo-square opening to prevent undesired action on said
microswitches by allowing only limited deviations of said
shaft.
2. An aircraft video system in accordance with claim 1, further
characterized by
a second radome formed in a rearward portion of said technical
container,
a slave camera in said second radome, connected to said television
monitor screen,
a second cradle pivotly supporting said slave camera,
limit switches controlling reversing switches located for actuation
by said pilot and slave cameras to permit selection of a pertinent
video display from one of said cameras, and the switching off of
the unused camera.
3. An aircraft video system as in claim 2 wherein at least said
pulleys linked to said camera and said cradle are also connected to
potentiometers providing electrical information relative to the
position of the camera.
4. An aircraft video system in accordance with claim 1, further
characterized by
said remotely controlled means further including
servo amplifiers controlling said electric motors,
potentiometers mounted in said remote-control box and connected to
said servo amplifiers.
5. An aircraft video system utilizing an aircraft and operation on
board intended for air surveyance of ground activity comprising
a technical container attached to the aircraft,
a transparent radome forming a forward portion of said
container,
a pilot camera inclinable in angle of sight and azimuth located in
said radome,
a television monitor screen in the aircraft connected to said
camera,
a remotely controlled inclination means for controlling inclination
and for controlling the object-lens of said camera in said radome
connected to said camera,
a television transmitter connected to said camera,
said remotely controlled means including
a cradle connected to said container,
a first means for pivoting said camera in azimuth with respect to
said cradle,
a second means for pivoting in sight said cradle with respect to
said container,
electric motors connected to said camera, and to said cradle,
a remote-control box connected to said remotely controlled means
located to be acted upon by instinctive reaction of the operator
while observing said television monitor screen,
said remote-control box including
a pivoted axis shaft,
microswitches controlling said electric motors for controlling
camera inclination,
said shaft having a portion which acts upon said microswitches a
plate in said box havng an opening therein,
said portion of said shaft having protuberant parts on either side
of a portion of said shaft itself included in said opening to
prevent undesired action on said microswitches by allowing only
limited deviations of said shaft.
Description
When the activities on the ground are surveyed by means of an
aircraft equipped with a video system, the latter may comprise a
stabilized platform to eliminate instability effects resulting from
the aircraft motions.
Moreover, when the usual video equipments are to be made
operational aboard a light aeroplane, a so-called "aircraft" system
must be developed, i.e. a system which is lightweight, as little
cumbersome as possible, reliable and easy to operate.
The means employed heretofore and those known in this field to the
Applicant do not meet all these requirements because the stabilized
platforms which are generally used are heavy and cumbersome and
cannot be installed aboard a light aircraft such as, for instance a
touring aeroplane.
However, there are cases in which the utilization of a light
aircraft equipped with a video system is very desirable. It is the
case, for instance during surveyance of the road traffic when the
observation is effected by an operator aboard the aircraft, while
transmission of images is effected in the direction of the ground
toward an operational headquarter which can itself be mobile, for
instance on a video truck.
If, for the above reasons the stabilized platform has to be
eliminated, means have to be provided for compensating for the
instability effects resulting from aircraft motions but these means
must remain lightweight, simple to operate and little
cumbersome.
To substantiate this, it will be noted that an exemplifying system
as described in the French patent application 2,069,852, comprising
a platform stabilized by at least three gyroscopes and angular
deviation measuring devices, cannot at all be adapted for
installation aboard a light aircraft due to its weight, bulkiness
and intrinsic complexity.
The usual video systems can be used but to eliminate servitudes of
the abovementioned type it is necessary to be able:
to take advantage of simple means for remote control of the TV
camera, to produce, instinctively, spatially stable images taking
into account the attitude of the aircraft, with possible focusing
and enlargement of the image of those items which the operator
wants to more particularly observe;
to constitute a removable and easily adaptable, aircraft technical
unit; and
to integrate all the parts of the display units into a homogeneous
assembly, both aboard the aircraft and on the ground.
SUMMARY OF THE INVENTION
It is therefore an object of this invention to provide a method of
remote control of a lightweight aircraft video system for the
surveyance of activities on the ground, which associates in a
homogeneous combination the whole of the required means thereby to
permit production of spatially stable images with controlled field
of vision.
The invention has also for its object the combination of means for
carrying out the method, which substantially comprises a removable
technical container aboard the aircraft including a TV camera
remotely controlled from the pilot's cockpit and a TV transmitter,
on the one hand, and on the other hand, in the cockpit, a
remote-control box and a TV monitor screen and, on the ground,
complementary equipment such as a TV monitor receiver as well as
the usual members contained in a technical unit.
Additional features, advantages and objects of the invention will
appear from the following description in which possible forms of
embodiment of the invention have been set forth in detail in an
explanatory and not limitative fashion in the accompanying
drawing.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic view illustrating the combination of means
utilized according to the invention;
FIG. 2 is a partial schematic view of the pilot's cockpit aboard
the survey aircraft, according to FIG. 1;
FIG. 3 is a partial schematic view showing the installation of the
TV camera within the aircraft technical container according to FIG.
1;
FIGS. 4 and 5 are respective side and plane views of the remote
control lever of the TV camera;
FIGS. 6 and 7 are electric diagrams of the assembly aboard the
aircraft; and
FIG. 8 is a schematic view of another form of embodiment with two
cameras.
Referring to FIG. 1, the installation consists as a whole of a
light aircraft A supporting, for instance under its right-hand
wing, a technical container I comprising the TV camera, remotely
controlled and orientable in angle of sight and heading, with zoom
and diaphragm adjustment, on the one hand, and on the other hand, a
transmitter 27 retransmitting images to the ground in the direction
of an equipment which comprises an orientable aerial 2 connected to
a technical centre in which there are a TV receiver 3, a monitor
video unit 4, an aerial servo-control or remote-control box 5, a
VHF microphone 6 and a magnetoscope 7. The transmission aerial lies
at the most suitable place for hertzian transmission.
Aboard the aircraft A, as shown in FIG. 2, the pilot's cock-pit
includes a video monitor screen 8 and a remote-control box 9 for
controlling the TV camera.
The technical container 1 comprises in its forward portion as shown
in FIG. 3, a transparent radome 10 for protecting the TV camera II
and its mechanisms of sight and azimuth drive.
For the intended purpose the camera II is movable in
righthand-lefthand rotation (azimuth) within a cradle 12 about axis
x,x' substantially parallel to the aeroplane axis.
The cradle 12 is itself movable in up-down (angle of sight)
rotation within a cradle 13 secured to the container, about the
axis y,y' substantially perpendicular to the aeroplane axis.
Elastic suspension means 40 are used to insulate from vibrations
the cradle 13 supporting camera II.
Obviously, in this type of installation displacement of the camera
is maximal in both directions and remote-control can be provided
simply by means of two mechanisms in the manner described
hereinbelow in reference to FIG. 3.
A first azimuth-rotation mechanism comprises a motor with a pulley
14 connected to cradle 12, a pulley 18 connected to the camera II
and a transmitting cable 28 passing through a tension regulator
constituted by an S-shaped tubular part (not shown).
A rotary potentiometer 15, the function of which will be explained
hereinafter and which is connected to the cradle 12, is also
connected by a cable 29 to the pulley 18, said cable also passing
through an S-shaped tension regulator (not shown).
A second mechanism, for sight-rotation, similarly comprises a motor
with a pulley 17 connected to the cradle 13, a pulley 19 connected
to the cradle 12 and a transmitting cable 30 passing through a
tension regulator constituted by an S-shaped tubular part (not
shown).
A rotary potentiometer 16, the function of which will be explained
later and which is connected to the cradle 13 is also connected
through a cable 31 to the pulley 19, said cable also passing
through an S-shaped tension regulator (not shown).
A standard electrical remote-control unit for object-lens (zoom and
diaphragm) focusing is further mounted on the camera in a manner
known per se.
Control of the motors 14 and 17 of the mechanisms is effected in
the manner described hereinafter in reference to FIGS. 4 and 5 and
the electric diagram of FIG. 6.
The remote control box 9 comprises a remote control lever 19 A on
the one hand, and on the other hand a reversing switch for
controlling the zoom motor 32 and for controlling the diaphragm
motor 33, whereas an ON-OFF switch 34 for the TV transmitter is
connected to the aeroplane bus-bar.
The remote-control lever 19A is formed with a joint axis 20 lodged
in an elastic suspension 21 and its angular displacement takes
place about an imaginary virtual point P.
A perforate plate 22 limits displacement of said axis 20 which in
its turn permits its lower portion to actuate microswitches 23, 24,
25 and 26 which are connected to motors 14 and 17 for orientation
of the camera II according to the diagram of FIG. 6.
In this way, as shown in detail in FIG. 5, the lefthand motion of
axis 20 will, for instance move said lower portion toward
micro-switch 23 which will feed motor 14 in the proper direction
for moving camera II to the left-hand side.
Two conjugated actions are possible in view of the pseudo-square
opening in plate 22 which actually permits conjugated action, for
instance, on both micro-switch 23 and micro-switch 24 thereby
bringing the camera into a forward left-hand orientation.
The displacements of axis 20 are limited, due to the special
configuration of its active end 20A-20B, which is protuberant on
both sides of its median portion, itself included in the opening of
the plate 22 such that any undesired action upon the micro-switches
is prevented.
The potentiometers 15 and 16 can provide electrical information
representing the angular sight and azimuth positions of the camera
II.
Moreover, limit switches (not shown) set boundaries in both
directions to the displacement of the camera.
In another form of embodiment shown in FIG. 7, the control unit of
the motors has been replaced by an amplifier unit.
In this arrangement the remote control box 35 comprises
potentiometers 35A-35B having cursors linked to axis 20 and
connected to servo-amplifiers 36, 37 which supply power to the
motor 38 for control of angular sight on the one hand, and on the
other hand to the motor 39 for azimuth control.
Furthermore, return springs 35d and 35e are used for bringing the
lever 20 to the median point.
It will be noted that the operator in the pilot's cockpit has at
his disposal simple means for instinctively stabilizing the image
on the one hand and on the other hand means for acting upon the
image to possibly show more clearly those items on the ground which
he wants to observe with more attention.
Thus the normal motions of flight--pitching, rolling and yaw--will
be compensated for in the image transmitted to the ground for the
benefit of the observer in so far as the operator was able to act
instinctively upon the available controls, namely the
remote-control lever and/or the zoom and diaphragm controls.
This artificial stability can be preserved even in the event that
enlargement of the image should be desired to perceive details on
the ground, and thus closer enquiry can be made either on the
operator's initiative or on his receiving instructions from the
ground or also on direct remote control signal being transmitted in
duplex by the observer at the central station.
When the operator wishes to extend the observation to beyond the
optical field permitted by the camera II mounted in the container
I, the other form of embodiment outlined in FIG. 8 can
advantageously be utilized.
According to this form of embodiment the camera II disposed at the
front of the container I becomes the "pilot" camera. A second
camera II', the "slave" camera, is added to the pilot camera II,
said slave camera being lodged in a second radome 10' mounted at
the rear of the technical container I. The second camera II'
permits extension of the optical field in the rearward direction.
For this purpose, the camera II' is provided with remote-control
means similar to those of camera II.
Both cameras in their respective cradles then act upon respective
limit switches 40 and 40' controlling reversing switches to permit
selection of the appropriate video image (pilot or slave camera)
and switching off of the unused camera.
In other words, when the pilot camera reaches the vertical limit V
the slave camera is brought into operation under the action of the
pilot camera limit-switch thereby replacing the pilot camera for
the continuity of the observation in the rearward direction, this
replacement occurring of course both ways.
Moreover, the hertzian connections are produced in the usual manner
both for the image and the sound, which are demodulated on the
ground; similarly, normaly VHF connection is used for communicating
instructions.
Therefore it is clear now that the invention provides such a
homogeneous combination of means by which the abovementioned
objects can be achieved.
This combination authorizes the employment of generally known means
which, to the applicant's knowledge, have heretofore never been
assembled in this manner. Therefore a simple unit is provided which
permits air surveyance under proper conditions for transmitting
images within a range of 30 km from a plane flying at a height of
about 300 m and of more than 80 km when the plane flies at 1000
m.
This invention has, of course, been described and represented by
way of a preferential embodiment only and equivalents to its
constitutive elements can be substituted therefor without departing
from the scope of the invention which is defined by the following
claims.
* * * * *